Boat Amp Issues - Please Help

(alteczen) · (alteczen) **Join Date: Aug 2003** 05-30-2006, 1:29 PM

I need some help from the Electronics and Audio gurus...

I have an '04 X-Star that has the standard factory 2 battery (blue top Optimas) setup on a switch (1, 2, or both). I've changed the amp setup to the following:

6 channel JL e6450 powering 6 boat speakers (polk momo)
4 channel JL e4300 powering 4 tower speakers (polk momo)
mono block JL 1400D powering sub (polk momo 10")

All three have seperate power lines from the batteries with inline fuses.

I've blown the 4 channel and mono block amps. They turn on, show green lights that everything is working but they aren't giving output. I took them to a JL dealer and they confirmed they are blown.

After describing my setup they say that I could be starving the amps for power by only have 2 batteries and this could be the cause of them blowing. They are recommending (without seeing the setup in person yet) that I need more battery power or a capacitor...

Could this be the issue? I don't want to pay $400+ to add battery power and have them fix my issues if it's not going to fix the problem.

I appreciate the feedback...

(acurtis_ttu) · (acurtis_ttu) **Join Date: May 2004** 05-30-2006, 1:55 PM

No offense but your system is not that big, sounds like a bad batch of amps. you have a very common size system. What size wires are you running to your amps? Adding more batteries will not give your more "power" just increase yrou run time. Cap's act as very short term power storage devices (milisecond fast) but will not help a power problem. That is definately not your issue. Were the amps running and then blew or were they off then you turned your boat off and no sound?

What coudl have happened is you let your batteries get down very low, still cranking on your system, that could fry an amp. An extra battery woudl have helped then, possibly, but most amps will shut down before they blow.

(brucemac) · (brucemac) **Join Date: Dec 2005** 05-30-2006, 3:13 PM

yeah, i'm no expert, but i'd tend to agree with adam. something else must be going on.

i run the e6450m against 4 momo's and 2 db1000 tweeters and then an e1200 against a 10w3v2. i've had no problems thus far and i'm running all that off of 1 blue top (with a 2nd off of a combiner and switch).

(alteczen) · (alteczen) **Join Date: Aug 2003** 05-30-2006, 5:34 PM

First off - thanks for the replies...

The sub amp was running when it blew. I was riding at the time so I don't know what exactly happened. I got in the boat and noticed we had no bass after about 10 minutes. The sub would put out a low hiss and that's it.

The tower amp's (4300) remote switch is what is messed on it. The amp won't turn off when the remote wire tells it to so it will just drain the batteries unless you diconnect it's power line. I'm guessing this is just a mfg issue and not something in the boat.

I had my doubts that lack of battery power was the issue so that's why I thought I would get a second opinion from people who don't have $ on the line. I guess I'll just wait for the amps to be returned to me from warranty and cross my fingers...

Thanks again for the help.

(acurtis_ttu) · (acurtis_ttu) **Join Date: May 2004** 05-31-2006, 7:17 AM

sounds like a couple of bad amps. I have a similar power drain issue on my jl 500/1. I have to switch the power breaker off or the amp will pull power. It's something in the amp. The amp works fine other than that.

(bob) · (bob) **Join Date: Feb 2001** 05-31-2006, 10:08 AM

Maybe heat? How are you cooling the amps and how many times have they shut down from an over-heat condition? This can also be a direct result of low voltage causing the drivers to cook themselves while trying to maintain the sound level.

(alteczen) · (alteczen) **Join Date: Aug 2003** 05-31-2006, 12:26 PM

bob...

I've never had them shut down due to heat. They are mounted on the inside wall of the passenger side on the xstar and it is fairly well ventalated.

However you are the first to mention that low voltage could be an issue - which is what the local stereo place said sounds like the problem. can you elaborate on this? How can I test this and what is the solution (adding another battery...?) ?

Thanks...

(Message edited by alteczen on May 31, 2006)

(acurtis_ttu) · (acurtis_ttu) **Join Date: May 2004** 05-31-2006, 12:41 PM

See above

"What could have happened is you let your batteries get down very low, still cranking on your system, that could fry an amp. An extra battery would have helped then, possibly, but most amps will shut down before they blow."

your amps will msot likely start to clip when they get in a low power situation. B/c jl amps have a regulated power supply (produce same output regardless of input) they will usually shut down if voltage is low, but as voltage drops amp draw dramtically increases (play with ohm's law formula). When you have really high current draw you will start generating excess heat. you could fry the power supply by starving it from power, but unlikely as the protection would have come on....we're talkign abtou high quality amps, but even they have lemons.

(mikeski) · (mikeski) **Join Date: Aug 2003** 05-31-2006, 8:47 PM

What size power wire are you running to the amps? How hot are they getting? Are they mounted with the heat fins up? Where are your crossovers set?

Most speakers have rising impedence down in the 60-70hz range, it's better if you steer clear of that range with everything but the subs. If your wiring is undersized you might be seeing low voltage at the amps.